Ovarian cancer is a silent killer with few early symptoms and advanced disease present at the time of diagnosis. This cancer is the most lethal of all gynecologic malignancies with over 20,000 new cases diagnosed each year. The 5 year survival rates for ovarian cancer dramatically improve when the disease is diagnosed at an early stage. Therefore, the long term goal of the Glycomics Laboratory for the Early Detection of Epithelial Ovarian Cancer is to apply the most advanced technologies toward the goal of identifying glycoprotein and glycan markers that can detect ovarian cancer early. We are a multidisciplinary team with expertise in proteomics, glycomics, and immunology from investigators at the Penn Ovarian Cancer Research Center at the University of Pennsylvania (UPENN) and the Complex Carbohydrate Research Center (CCRC) at the University of Georgia. The co-investigators at the CCRC specialize in the mass spectrometry identification of glycan and glycoprotein biomarkers from complex human tissue and serum samples. The co- investigators at UPENN specialize in preclinical validations, antibody production, and the development of biomarkers for ovarian cancer. The aims of this application are (1) Assay development with phase II and phase III validations of previously identified glycosylation modifications on identified biomarkers for EOC, (2) Glycomic identification of new EOC glycoprotein biomarkers, (3) Functional studies to understand the role of GPI anchored protein modification in the development and progression of EOC.